document.write( "Question 244861: Five years ago a girl was one-half as old as her brother was then,and now she is three years younger than he is.Find their present ages. \n" ); document.write( "
Algebra.Com's Answer #179022 by dabanfield(803)\"\" \"About 
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Let B represent the boy's current age and G the girl's current age:\r
\n" ); document.write( "\n" ); document.write( "We know that now the girl is 3 years younger than the boy so:\r
\n" ); document.write( "\n" ); document.write( "G = B - 3\r
\n" ); document.write( "\n" ); document.write( "Five years ago the ages were B - 5 and G -5. We know that back then the girl's age was half the boy's so:\r
\n" ); document.write( "\n" ); document.write( "(B-5)/2 = (G-5) or
\n" ); document.write( "(B-5) = 2*(G-5)\r
\n" ); document.write( "\n" ); document.write( "Substituting B-3 for G in the equation above we have:\r
\n" ); document.write( "\n" ); document.write( "(B-5) = 2*((B-3)-5)
\n" ); document.write( "B-5 = (2*B) - 6 - 10
\n" ); document.write( "Simplifying we have:\r
\n" ); document.write( "\n" ); document.write( "-5+16 = (2*B) - B
\n" ); document.write( "11 = B\r
\n" ); document.write( "\n" ); document.write( "Substituting B = 11 in the current ages equation, B = G-3, we have 11 = G -3 or G = 8.\r
\n" ); document.write( "\n" ); document.write( "The Boy is 11 and the girl is 8.
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